Means for forming expansion joints in roadways



Filed Feb. '7

ff L75:

H R. GUNDLACH MEANS FOR FORMING EXPANSION JoINTs lIN ROADWAYS Feb. 19 1924.

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Patented Feb. 19, 1924.

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HENRY R. GUNDLACH, F BALTIMORE, MARYLAND, ASSIGNOR T0 THE UNITED STATES l ASPHALT REFINING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF SOUTH DAKOTA.

MEANS FOR FORMING EXPANSION JOIN TS IN ROADWAYS.

Application iled February 7, 1922. Serial No. 534,738.

To all whom t may concern.'

Be it known that HENRY R. GUNDLACH,

a citizen of the United States, residing at Baltimore, in the county of Baltimore and State of Maryland, has invented new and useful Improvements in Means for Forming Expansion Joints in Roadways, of which the following is a specification.

The present invention relates to road construction, and particularly to roads built of concrete and like` material. It has particularly to do with the expansion joints of such roadways, and its specic object is to provide -a convenient and efficient means for l makin such joint.

In t e 'building of concrete roadways, it is necessary to make provision for the expansion and contraction of those roadways under changing temperatures. High temperatures cause expansion, which, unless compensated for, will fracture the roadway and result.

in its breaking up and deterioration. It is customary, therefore, in the making of such roads, to provide, at intervals, expansion joints which will give the necessary compensation and permit the expansion of sections of the road without danger of cracking, with the resultant disintegration which rapidly follows anyfracture of the concrete material. Heretofore, it has been proposed to form these expansion joints by placing between the ends of adjacent sections, or the fixed curbing and the concrete bed or roadway, material which will yield under the action of the expanding concrete, and one common method'of doing this is by pouring between the ends of adjacent sections or the fixed curbing and the concrete section a yielding material, such as asphalt. This method is not economical, as it requires the constant use of an asphaltpot and fire for keeping the asphalt liquid, and the labor incident to forming the joints in this manner is very considerable.

The purpose of my invention is to provide a joint unit which may be manufactured and sold by the asphalt maker to the road builders, which unit is so constructed that it may be readily handled and quickly placed without danger of distortion under varying temperatures or careless handling,-

but whlch w l, when properly placed in the roadway, fulfill all of the requirements necessary for the expansion joint between roadway sections, or between foundation sections of concrete, or between roadway sections or foundation sections' and iixed independent curbing.

I accomplish this object by providing a slab or board of asphalt mixture which is reinforced by a core of material. of greater rigidity than the asphalt of which the slab is than those herein disclosed may be adoptedand still be within the range of this development.

In the drawings F'g. 1 is a view in side elevation of a slab embodying my invention.

Fig. 2 is a sectional view upon the line 2--2 of Fig. 1.

Fig. 3 is a view similar to Fig. 2, showirllgba different form of insert or core for the s a Fig. 4; shows conventionally a roadway wlith the expansion joint forming slab in p ace.

Fig. 5 shows a roadway of different construction, namely, with a concrete base, with the expansion joint forming slab in place.

Fig. 6 is a sectional view. illustrating the application of the means between a roadway and a fixed and independent curbing.

Referring to the drawings by numbers,

substantially like numbers indicating like parts lin thejoint forming' It will be understood that I do not confine myself, however, to any particular dimensions, as these may be varied, according to the needs of the work and the factor of ex'- pansion to be taken care of.

The slab' 10 will be formed of an asphalt mixture which may be varied to meet the demands of the work or the requirements, either legal or otherwise, of the particular State or locality where the material is used, the requirements, in different sections of the country, as to penetration, solubility, melting point, and the like, varying considerably.

I preferably use blown asphalt as distinguished from steam refined asphalt, for the reason that blown asphalt, having' the same penetration as steam refined asphalt, has a melting point considerably higher, it having been found that blown asphalt, under the ring and ball test, will stand a temperature of 180 F., whereas steam refined asphalt will stand a temperature, under the same test, of only 130 F.

As indicated in dotted lines in Fig. 1 and in full lines in Fig. 2, the slab 10 is provided with an insert or core 11 of material of greater rigidity than the asphalt, the core 11 being preferably of metal, and, in its simplest form, being a metal sheet of from 20 to 26 gauge. The core 11 will be, preferably entirely enclosed in the asphalt as shown, it vextending lengthwise nearly to the ends of the asphalt slab 10, there being a clearance or covering vof asphalt -approximately onehalf inch at the ends of the core or insert. There will be, at the sides of the core or insert 11, a greater clearance, it being preferable to leave substantially one inch of clear asphalt beyond the sides of the core 11 so that the side edges of the slab 10, which are, of course, exposed to traflic, will not be worn down to the extent that the side edges of the core willbe exposed. Preferably, the core 11 will be centrally placed with respect to the thickness of the slab, as this gives a better balanced structm'e than .if the core is asymmetrically placed in the slab.

Slabs constructed as hereinbefore described and as illustrated in the drawings may be manufactured at the plant and shipped in quantities to the point of use without danger of their breaking down or becoming distorted, the core supporting the asphalt covering and retainingN it in shape so that always ready for insertion in the roadway as indicated in Fig. 4. As there shown, the slab 10 will be inserted between the adjacent ends of the road sections, and these slabs will be spaced along the roadway at intervals, as often as the conditions may demand or the local requirements may call for.

The permanent form of the slab permits it to be readily handled and placed 1n position, and when once located, it gives proper more,

it will not Warp or curl, but will be compensation for expansion of the roadway sections. There is a sufficient body of asphalt surrounding the core to take care of the expansion and contraction of the concrete sections of the road, the core, while being of suiiicientrigidity to give to and retain the permanent form of the slab, being of such character that it does not interfere with the yielding of that slab under expansion strains.

In Fig. 5 I have shownl the slab as applied to a concrete foundation, over which foundation may be laid an asphaltic or otherwise suitable surface.

In Fig. 6 I have illustrated the use of the slab between .a separate and fixed curbing and a concrete roadway, it being understood that the slab may be employed wherever it is desirable to compensate for expansion.

In the form of the invention shown in Fig. 3,*the slab 12.is provided with a core 13 of fluted or corrugated material, this core y13 being preferably of metal.

The advantage of this corrugated core 13 over the plain core shown in Fig. 2 is that it gives an anchoring relation between the core and the asphalt of the slab, and, furtherthe corrugated core 13 gives greater rigidity to the slab than does the plain core shown in Fig. 2. .A further advantage of the corrugated core 13 is that if excessive expansion should take place and the pressure upon the slab 12 should displace the asphalt more or less completely, the corrugated core 13 would, under this excessive pressure, flatten, and yield suiiciently under the pressure of the road sections to guard against any possible fracture of those road sections, even though the expansion reachedr the point where `there was compele displacement of the asphalt of the slab.

ere the corrugated core 13 is used, the peaks of the corrugations will preferably be covered by the asphalt to a depth sucient t0 take care of the ordinary expansion,'pref erably to the extent that the sum of the thicknesses of asphalt on the opposite peaks or high points will be not less than onehalf the thickness of the slab.

While I have shown, in Fig. 3, a'simple and uniformly corrugated sheet, it will be understood that the sheet may be Corrugated, ribbed, or provided with anchoring projections and flutings of different design and still be within the purview of my invention.

By following the invention herein disclosed, I amenabled to provide an expansion 3oint unit which may be'manufactured at the plant readily transported to the point of use, stored until needed, and then handled and placed b unskilled labor without any danger of its reaking down or becoming dlstorted underrhandling or under the usual temperatures.

Such changes in matters of design, dimensions or construction asare within the range of mechanical skill are', of course, to be regarded as within my invention.

I claim: A

1. A slab for roadway expansion joints, formed of asphalt, and having a stiening core of metal with corrugations running sion widthwise,

longitudinally ofthe slab to permit expanand spaced from the edges of the slab to provide wearing areas of appreciable width on each side of said core.

2. A slab for roadwaI expansion joints, formed of asphalt, and aving a stifening core formed of an imperforated metal sheet corrugated longitudinally to formlaterally extending anchoring projections.

3. A slab for roadwa expansion joints, formed of asphalt, and avin a stiffening core formed of an imperforate metal sheet corrugated longitudinally to form laterally exten nlli) expansion of said core widthwise of the s a 4. An expansion joint member for filling the expanslon joints of concrete and otherv ing anchoring projections and per.

mason structures consistin o f a lateral strip o bitummous mater1al aving narrow edge surfaces` and comparatively lbroad side surfaces, a -corrugated metal reinforcing member extendin longitudinally thereof and spaced away rom the' side surfaces, the corrugations extending longitudinally of the reinforcing member providing-for expansion and contraction transversely to the corru ations.

5. n combination with separated sections of a Aconcrete structure spaced to provide for contraction and expansion of said sections, an expansion joint filling member consisting of a strip of bituminous material having a reinforcing member imbedded therein and spaced away from the vsurfaces of said bituminous material -which engage the concrete, said reinforcing member being 'of corrugated metal, the corrugations extending in the direction of the length of said member.

In testimony whereof I have hereunto set m hand.

y HENRY R. GUNDLACH. 

